TOTEM Update BSM? Fredrik Oljemark (Helsinki Univ. & HIP) On behalf of the TOTEM Collaboration Jyväskylä, TOTEM p. 1

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1 TOTEM Update Fredrik Oljemark (Helsinki Univ. & HIP) b BSM? On behalf of the TOTEM Collaboration Jyväskylä, TOTEM p. 1

2 TOTEM Physics Overview Total cross-section Elastic Scattering b Forward physics Diffraction: soft and hard b jet jet Simone TOTEM Giani p. 2 p. 2

3 The TOTEM Experimental apparatus in RUN-2 (symmetric around IP5) T1, T2 telescope: Very forward detectors for tracking of charged particle produced in inelastic collisions (3-90 mrad) RP detectors: Silicon detectors placed in movable beampipe insertions, to approach the beam to less than a millimetre: detection of protons with scattering angles of only a few mrad Sector 45 (left arm) RP unit: 2 vertical, 1 horizontal pot + BPM Timing pots Tracking pots Horizontal RP Vertical RPs BP M Larger set of RP ever operating simultaneously in a collider: m stations relocated to 210 m (increased lever arm) RPs at 214 m rotated by 8 (multi-track capability) Two new horizontal RPs for timing detectors (CT-PPS, high luminosity) TOTEM p. Simone 3 p. Gia 3

4 TOTEM high luminosity data taking RP detectors previously used only in special TOTEM runs High β* (90m, 1km, 2.5km) Low angular beam dispersions ~Low luminosity (wide beam) Short runtime (few weeks/year) Integrated luminosity size O(pb -1 ) Common running with CMS, trigger bit interchange CTPPS reach AQGC with CEP WW: comparison with current best limits TOTEM p. 4 p. 4

5 TOTEM high luminosity data taking Now in Run-2, RP s commissioned for insertion during all regular high luminosity runs Low β* CTPPS: RP s fully integrated in CMS Excellent for central diffraction: exclusive W + W - or γ γ/zz/z γ with mass measurement from protons. AQGC: non-sm 4-gauge boson vertices Collected ~15 fb -1 this year Mass threshold higher (few hundred GeV) First stage CTPPS: use existing detectors for tracking Present RP detectors Si, not rad hard Before HV increase After Most beam halo protons hit very small area, increase life by moving pot up/down by 2mm Performance recuperated by increasing the voltage Replace with rad-hard 3D Si (RP214: 2017) Only horizontal pots inserted during low β* runs TOTEM p. 5 p. 5

6 TOTEM upgrade with timing detectors One prototype diamond plane CTPPS diamond plane RP210 Timing detectors have been installed inside the RPs at 210m, on the two sides of the IP. Detectors based on diamond (rad hard) sensors, expected <50 ps time resolution per arm (measured 80 ps per plane). Detector readout in commissioning For CD events the difference of the arrival time of the protons gives the longitudinal vertex position. Only way to associate the proton vertex to the CMS one. Background suppression and possibility of common runs at higher pile-up with CMS TOTEM p. 6 p. 6

7 TOTEM special 13 TeV (Sept 2016) New beam optics β*=2500m to have very low t-acceptance limit ( to 0.2 GeV 2 ) Analysis starting, elastic event sample ~7 M Elastic main interest, T1 & T2 not on during run Measure ρ parameter At small enough t the pp scattering is also affected by the Coulomb interaction: low-t Odderon would affect ρ, existence deducible from measured ρ- value (smallest angles = needs highest β) TOTEM p. Simone 7 p. Gia 7

8 Central diffractive productions: = Glueball? TOTEM special Runs: Physics A few examples of what we can learn from these data: Glueball (discovery potential): particle consisting only of gluons Predicted by QCD, searched for decades, never confirmed, but: Lattice QCD predicts the lowest possible masses Central diffraction is mediated by gluons, natural place where to find it: 0 ++,2 ++ favoured. By tagging the protons: 100% sure of the process exclusivity (nothing lost by the central detector) (~high luminosity & β=90m: Oct bunch ~0.4pb -1 ) Elastic scattering: p1 p1 = p1 Very large-t scattering: QCD based models can be used to describe the process 3 individual gluons mediating the elastic interaction (if J PC =1 --, this would be a high-t Odderon) (~high luminosity; exponentially falling spectrum) p2 p2 = p2 TOTEM p. Simone 8 p. Gia 8

9 New results on differential elastic cross section ds/dt at low 4-momentum transfer t Pure exponential ds EL /dt excluded with unprecedented significance (>7s) ds EL /dt Difference with respect to an exponential Hint for more than one channel at work in the low-t elastic scattering Pure Hadronic TOTEM p. Simone 9 p. Gia 9

10 New results on differential elastic cross section ds/dt at low 4-momentum transfer t By measuring the elastic scattering in the region of the Coulomb-Nuclear interference: Access to the Hadronic phase (sensitivity to the impact parameter description of the collision) b Data fit allowed a peripheral description of the elastic collision Centrality of the elastic collisions are possible but not necessary TOTEM p. Simone 10p. 10 Gia

11 New results on total pp cross section s TOT and r Thanks to the study of the Coulomb-Hadronic interference we can: Quantify and remove the effect of the electromagnetic interaction for a better determination of the hadronic one and its better extrapolation to t=0: s TOT =102.9 mb New, luminosity-independent determination of s TOT : consistent with the previously published by TOTEM (PRL 111, ) but this time no external parameter has been used Make the first determination of r at the LHC : r Re F Im F H H t 0 The precise knowledge of this parameter is needed by theory: discovery of a 3-gluon (J PC =1 - - ) state as mediator contributing to the elastic interaction. This data: it exists at 2-3s, Run-2 data will be crucial. To know more: CERN-PH-EP TOTEM p. Simone 11p. 11 Gia

12 RUN-2 Preliminary 13 TeV (PRELIMINARY) Models predictions: Transition to pqcd based models! No structure (dips/waves) observed after the first dip: Excluding vast majority of the theoretical models published in the last decades TOTEM p. Simone 12p. 12 Gia

13 Outlook High precision elastic differential and total cross section at 13 TeV. Lower energy analysis at 2.76 TeV. Sensitivity to J PC =1 - - three gluon colourless state from ultra low-t elastic scattering at 13 TeV. Central diffraction at 13 TeV: unique CMS+TOTEM apparatus to discover glueballs and study hard diffraction. Upgrade tracking with rad-hard 3D Si (see multiple tracks) Data-taking with the timing detectors for central diffraction at higher luminosity jointly with CMS Look for high-mass central system (BSM?) = Glueball? Stay tuned and thanks for your attention! TOTEM p. Simone 13p. 13 Gia

14 BACKUP

15 TOTEM special 13 TeV (October 2015) UPGRADED TOTEM trigger 80 KHz: capability x 50 with respect to Run-1 30h of stable beam, special 90m optics, m=7%-10%, up to 680 bunches (never before) CMS+TOTEM data TOTEM Triggers CMS Roman Pots Double Arm & T2 Veto Roman Pots Double Arm (TopTop/BottomBottom) T2 Min Bias, Zero Bias CMS Triggers TOTEM Dijets (P T threshold 20, 32 GeV) Dimuon Single m & HF veto. Integrated Luminosity LHC delivered: 0.74 pb -1 CMS recorded: 0.68 pb -1 TOTEM Trigger & CMS data: 0.55 pb -1 CMS + TOTEM data: ~ 0.4 pb -1 x 500 statistics with respect to the Run1 > 10 9 elastics candidates available >100M low mass central diffraction Unprecedented statistics for the study of the elastic scattering and of the central diffraction (including low mass resonances) TOTEM p. Simone 15 p. Gia 6

16 Non-exponential elastic dσ/dt In this range the elastic scattering is mediated by peripheral exchange of coherent gluonic systems Thanks to the high statistics data set (7M elastic events) the pure exponential behavior of the elastic scattering has been excluded Non exponentiality may suggest that more than one mechanism is at work. Pure exponential form excluded at 7.2 s significance. Pure exponential excluded for the first time with such large significance. TOTEM p. Simone 16 p. Gia 4

17 Hadronic-Coulomb interference Total cross section compatible with previous measurement (no external parameter used!) First measurement of the Coulomb/Hadronic interference and r at the LHC! TOTEM p. Simone 17 p. Gia 7

18 Hadronic-Coulomb interference Constant hadronic phase and exponential modulus excluded by the analysis Polynomial (>1 degree) exponential hadronic slope seems necessary for describe the data Both central and peripheral description of the pp scattering is compatible with data TOTEM p. Simone 18 p. Gia 6

19 Signal amplitude (V) TOTEM upgrade with timing detectors First detector test in the tunnel (Nov 2015): The first timing detector package has been tested inside the tunnel. Good test for the full system : noise was found to be compatible to the one measured in during the tests. Stable temperature and pressure for all the data taking period ~20h (pp at 5 TeV). Time resolution measurement compatible with the project specification. Two full diamond boards were installed in RP210 pots (Jun 2016): Installed during TS1, for CTPPS; working. Detector readout to be fully commissioned soon. Event display of one LHC shower (2015) Time sample (100 ps) TOTEM p. Simone 19p. 11 Gia